CVE-2025-39764

In the Linux kernel, the following vulnerability has been resolved:

netfilter: ctnetlink: remove refcounting in expectation dumpers

Same pattern as previous patch: do not keep the expectation object

alive via refcount, only store a cookie value and then use that

as the skip hint for dump resumption.

AFAICS this has the same issue as the one resolved in the conntrack

dumper, when we do

if (!refcount_inc_not_zero(&exp->use))

to increment the refcount, there is a chance that exp == last, which

causes a double-increment of the refcount and subsequent memory leak.